If you set up the ninth harmonic on a string fixed at both ends, its frequency compared to the seventh harmonic

A tuning fork vibrating with a sonometer having $20\,cm$ wire produces $5$ beats per sec. The beat frequency does not change if the length of the wire is changed to $21\,cm$. The frequency of the tuning fork must be ..... $Hz$

A pulse or a wave train travels along a stretched string and reaches the fixed end of the string. It will be reflected back with

A wire of length one metre under a certain initial tension emits a sound of fundamental frequency $256 \,Hz$. When the tension is increased by $1 \,kg$ wt, the frequency of the fundamental node increases to $320 \,Hz$. The initial tension is ........... $kg \,wt$

Which order of harmonics is missing or absent in case of stationary sound waves produced in a closed pipe ?

A $1 cm$ long string vibrates with fundamental frequency of $256\, Hz$. If the length is reduced to $\frac{1}{4}cm$ keeping the tension unaltered, the new fundamental frequency will be